Lucky you - Lodore is my favorite trip! Since you are launching during "high" season, you are only allowed 4 days (you can apply for an additional day at a charge of $35, I think, but this usually screws you as far as campsites and is not a sure thing to get it). The Dinosaur Ranger Office assigns your campsites so, if you've got Rippling Brook (I assume?) and Jones Hole (which #?) you should have another one assigned. At low flow, which you should expect, given the (lack of) snowpack, I'd recommend Cove or Island Park which will still be a haul, but camping at Jones Hole your last night makes for a very long day to the takeout. I use the Evans & Belknap Dinosaur River Guide which is as good as any I've seen as far as river maps. And, there is a groover dump right at the Split Mountain take-out, so you should be all set.
I think that addressed your questions - have a ball